Gauge and method of making the same



Sept. 12, 194.4. R. JOHNSON GAUGE AND METHOD OF MAKING SAME Filed .May 26, 1942 m mfm 7 fitter-neg,

Patented Sept. 12, 1944 UNITED STATES PATENTOFFICEA GAUGE AND METHOD OF MAKING V H I THE SAME Leighton R. Johnson, Minneapolis, Minn.- Application May 26, 1942, Serial No. 444,529 I 6 Claims.

This invention relates to a gauge and method of making the same, and particularly to a gauge for certain tools such as a tapered or cylindrical 15001. I

While the invention might be applicable to various kinds of tools, in the embodiment ofthe same illustrated it is shown as applied to a tool such as a tapered punch. Such punches are used in large numbers in certain ammunition factories and otherplants and there is usually a large number of different sizes. A gauge for such a punch comprises a tapered socket and to make such a gauge on the machine tools available for the purpose is a diflicult operation and one requiring quite a little time. It is difiicult to get the socket of the required size and precision.

It is an object of this invention to provide a very efiicient gauge and a simple and rapid method of making the same.

It is a further object of the invention to pro- ,vide a very efiicient and accurate gauge which [comprises a socket or tapered socket which is made without the use of machine tools.

It is another object of the invention to provide a very accurate and eflicient gauge which is made by plating metal upon the tool for which the gauge is made. 7

It is still another object of the invention to provide a very accurate gauge and a rapid method m ters refer to similar parts throughout the several views and in which:

Fig. 1 is a view in side elevation of a punch which the gauge is made;

Fig, 2 is a view in side elevation of said punch after one step of the method has been performed;

Fig. 3 is a partial vertical section through a portion of the punch shown in Fig. 2 and shown on quite an enlarged scale;

Fig. 4 is a View in side elevation of the punch after a further step of the method has been performed thereon;

Fig. 5 is a central vertical shell or casing used; Y

Fig. 6 is a central vertical section through the gaug enclosed in a casing; I

Fig. '7 is a vertical section taken on' line '|"l section through a of Fig. 6;

for

punch shown in Fig. 4 and shown on quite an enlarged scale;

Fig. 9 is a view similar to punch in the gauge;

Fig. 10 is a view in side elevation .of the finished gauge; and a Fig. 11 is a vertical section taken on line I ll'l ofFig.10. v Referring to the drawing a method is illustrated for making a gauge for atool such as shown in Fig, 1. It is usually desired to have a gauge with some tolerance or in other words, to have the gauge somewhat larger than the tool with which it is used. It'is a rather common practice to permit the finished tool to vary two or three ten-thousandths of aninch from the standard tool. In making thegauge with toler- Fig. 6 showing the ance the tool 20shown in Fig. 1, having the ta- 7 pered end 20a and the adjacent cylindrical portion 201) is first plated by the electro-plating process to place a very thin plating '2] on th operative end of the tool. This layer is usually of copper although other metals such as chromium might be'used. The layer 2| of plating is made a permanent layer, orone which cannot be bodily removed from the tool. Such electro-plating is usually done with a, current of high voltage and low amperage. Thecoating '2I is quite thin. Such coating can b made practically one-millionth of an inch in thickness. In practice however, the thickness would vary according to the tolerance desired in the gauge. A layer with a thickness of one-half of a ten-thousandth of an inch would be a good example.

After the coating 2| has been applied another layer 22 of metal is plated on the coatin 2| and this plating will b of the removable type such as commonly used in electro-typing; This is done with a current of low voltage and high amperage. Preferably an initial thin coating of nickel is first applied and then copper is applied to make a coating of substantial thickness so that a shell 23 is formed. The shell 23 comprises both the thin nickel and the heavier copper layer which become integral and are removed together. The

thin coat of metal 2| which is used for tolerance portion 22a and the thicker copper portion 22b.

After the coating 22 ha been applied to form the shell 23 the punch or tool 20. can be removed and the shell 23 can be used as-a'gauge or placed in any suitable holder to be used as a gauge. One convenient form of holder is to use a casing or I ,ing 2| could be ground therefrom. The gauge of 3 shell 24 such as shown in Fig. 5. The shell 23 with or without the tool 20 therein is placed centrally within the shell 24 and some substance 25 adapted to harden in fluid or semi-fluid form is placed about the shell 23 filling the casing 24. 5 Material 25 when hardened, thus. form a very efiective holding means for shell 23. In practice the material 25 has been of the electro-typing metal but various substances could be used such as hard resin, Plaster of Paris, etc. After the shell 23 is thus secured in casin 24 by the material 25 the shell 23 and casing 214 with the material therein is preferably cut so that a segment is removed therefrom as shown in Fig.;11. When-- the tool is placed in the gauge the fit of the tool; can be nicely observed along the line 23a formed.

by the inner wall of shell 23 and the side 24a of the cut-away shell and material, Y I 1 With the described method a very accurate'and' in fact, a practically perfect gauge is produced and the gauge is produced without the use of any machine tools in making the socketin ,.she11 23.

The desired tolerance can be had by varying the thickness of the layer 2|. If no tolerance is desired in the gauge then the coating 22 would be placed directly on the tool 20 and would be of the removable type. It will be understood or course,

that if the particular tool used in making.;the gauge i to be further used in practice the coatcourse,,wil1 be used for a. multiplicity of other tools which should have the dimensions of the .tool20. a

, From theiabove description it will be .seen'that I have produced a vejry accurate gaugeand a n :fnethod' of making the'sarne bymeans of which thegauge canbe ,yery rapidly produced. 'The time used in, making the gauge, is. only a small I fraction of. th t whichfwoul'd befrequired to produce a'gauge ofste'el or otherv metal on the 40 regular or ordinary machine tools. The gauges of the 'i'nventioncanthus'fbe rapidly and inexpensively made for" all "the 1 punches or other tools for which they}??? desired. A great saving in labor. is thusleffectedland a more accu- 5 rate gaugleproduced by the, methodoi-the inven- }tion than'could probably be produced by other methods.

I It willof course, be understoodth at various changes may be made', in the form det'ails 'ar- 5 .rangement and; proportions of the parts and in the steps and sequenceoi stepsjof,thejmethod, without'departing' from. thescope 'of applicants invention, which generally stated, consists ina method and device. capable .of carrying out i the objectsabove set forth, in the parts, ,and c om-- binations of partsldisclos'ed and defined: the

appended claims. a

will give a certain tolerance in said gauge.

2." The method of making a gauge for a tool which consists in plating a removable metallic coating on said tool of appreciable thickness to form a shell, embedding said shell in a. substance adapted to harden to form a holder for said shell and cutting away a. portion of said shell and holder along a longitudinal line to expose the interior of said shell so that the same can be used as a gauge.

'3. The method of, malcing a gauge for a tool of tapered or cylindrical form which consists in plating a removable metallic coating on said tool of appreciable thickness to, form a shell, embedding said shell in a holder and removing said shell from said tool, then cutting a segment from said shell and holder whereby the same formsa, gauge in which the fit of the tool .can be observed. 1

4. The method of making a gauge for a tool 0 of general tapered or cylindrical form which consists in plating a rem'ovablemetallic coating on 'said tool of appreciable thickness to form a shell and removing said shell .from said tool to be used as a gauge; cutting away a portion of said shell alonga longitudiinal line so that the fit of 1a tool infsaid gauge can be observed along said me. f v I 5. The method of making a gauge fora tool of tapered or cylindrical form which consists in platingon; saidtool a removable thin coating of nickel, then plating on. said nickel a coating of copper. of appreciable thickness whereby said nickel and"copper formla shell and removing said shell and using'the' same as a: gauge, em-

bedding said shen. in. a substance adapted to harden toforrn a holder creasing and cutting a segment from said shell and casing to form a gauge in which the tool can bejobserved.

6, A gauge fora tool comprising a tubular shell 0 having aninner very thin layerof nickel and an outer much thicker layer of copper secured thereon, said shell havinga portion cut away along a longitudinal element and airadial 'plane so. thatthe fit observed,

of atool placed therein can be TL'EIGHTON R. JOHNSON. 

